This invention generally relates to navigation or route guidance systems and, more particularly, to a navigation system that provides maneuver sequence notation adjacent each maneuver instruction and concatenates individual maneuver instructions to enhance the ability of a driver to correctly perceive a complex maneuver instruction.
Navigation systems generally provide a recommended route to a desired destination. Generally, the starting point and desired destination are selected from a large database of roads stored in a mass media storage, such as a CD ROM, which includes the roads in the area to be traveled by the user. If the navigation system is installed in a vehicle, the starting point is typically associated with the vehicle position and can be input to the navigation system by an associated position determining system that usually includes a GPS (Global Positioning System) receiver.
The navigation system determines a route to the destination utilizing an algorithm well-known to those in the art and currently in use in many navigation systems. Usually there are many potential routes between the selected starting point and the desired destination. Typical navigation systems select a recommended route based upon certain xe2x80x9ccostxe2x80x9d values associated with each segment of road in the road database. These cost values include the length of the road segment and the estimated time of travel through the road segment. The navigation system selects the potential route with the lowest total cost to be the recommended route. Depending upon the predetermined algorithm of the navigation system, the navigation system will recommend the route with the shortest total length, the lowest total time, or some weighted average of length and time.
The recommended route is then displayed to the user as a map showing the starting point and desired destination and highlighting the recommended route. Preferably, if the navigation system is installed in a vehicle, the navigation system displays the current position of the vehicle and provides visual turn-by-turn instructions to the driver, guiding the driver to the selected destination.
Many navigation systems also provide turn-by-turn instruction to the driver. The turn-by-turn instruction is typically selected from a database of predefined maneuver instructions such as a generic left-turn instruction, a right-turn instruction straight ahead instruction or the like. Highly congested and road intense environment such as a city may require two maneuvers in close proximity or other unusual maneuvers to continue along a recommended route. For example, a complex maneuver may require a second maneuver immediately after a first maneuver with an intersection located between the first and second maneuver. This can be confusing as the driver may have trouble identifying the maneuver instruction with the correct road. This is particularly troubling when a plurality of similar instructions are individually provided in a road intense environment.
It is thus desirable to provide a system for distinctively identifying maneuver instructions to enhance the ability of a driver to correctly perceive the maneuver instruction.
In general terms, this invention provides a vehicle navigation that provides maneuver sequence notation adjacent each maneuver instruction and concatenates individual maneuver instructions to enhance the ability of a driver to correctly perceive a complex maneuver instruction.
The navigation system generally includes a database of a plurality of roads, a position determining system, an input device, and a route determination system. The position determining system determines a position of the vehicle relative to the plurality of roads. The user selects a destination from the database with the input device. The navigation system then calculates and displays a recommended route directing the driver of the vehicle to the desired destination. Preferably, the navigation system displays turn-by-turn instructions to the desired destination.
As the vehicle approaches an upcoming maneuver the display switches from a large-scale map display view to a maneuver instruction view. The maneuver instruction view indicates to the driver the next maneuver to be performed along the recommended route to the destination.
During many simple maneuvers, such as an individual left or right turn, a single maneuver instruction representation, such as by a 3-dimensional turn arrow is displayed in a known manner. The maneuver instruction illustrates the upcoming maneuver to be performed along the recommended route to the destination. However, in some instances a user may be required to perform two maneuvers in close proximity or other unusual maneuvers to continue along a recommended route. Such complex maneuvers are typical in metro areas and may lead a user to incorrectly perform the maneuver. When such a complex maneuver is required the present invention switches to a complex maneuver instruction view which displays multiple maneuver instructions concatenated together to enhance the ability of a driver to correctly perceive a complex maneuver instruction.
Display of the complex maneuver instruction view is preferably related to the relationship of the upcoming maneuvers. The complex maneuver instruction view illustrates at least two maneuver instructions. Each maneuver instruction may comprise a 3-dimensional arrow superimposed on a 3-dimensional representation of the intersection. Preferably, as the user completes the first maneuver, the first maneuver instruction disappears and only the second maneuver instruction is displayed. In a disclosed embodiment, if a relative distance between two consecutive upcoming maneuvers is less than a predetermined distance, the complex maneuver instruction view is displayed. However, if these conditions are not met, a known single maneuver instruction view is displayed to separately display a maneuver instruction for each upcoming maneuver.
In another disclosed embodiment, the navigation system displays a plurality of maneuver sequence notations along the recommended route. The maneuver sequence notations are preferably alphanumeric such as xe2x80x9c1xe2x80x9d, xe2x80x9c2xe2x80x9d, xe2x80x9c3xe2x80x9d . . . , xe2x80x9cAxe2x80x9d, xe2x80x9cBxe2x80x9d, xe2x80x9cCxe2x80x9d . . . , or the like. The maneuver sequence notations indicate to the user the sequence and location of upcoming maneuvers along the recommended route. The maneuver sequence notation provides the user with a frame of reference as the user proceeds along a recommended route.
The maneuver sequence notation is preferably displayed both on the map display view and on the complex or single maneuver instruction view. In this way, the user immediately understands the upcoming maneuvers during the shift from the map display view to the maneuver instruction view.
The user is thereby provided with clear instruction through the complex maneuver and is less likely to incorrectly perform the maneuver. This is particularly advantageous in a highly congested or road intense environment such as a city.